Hong Kong's air quality continues to improve, bringing over 50 per cent reduction in long-term health risks
The Environmental Protection Department (EPD) announced today (March 21) an overview of Hong Kong's air quality in 2024.
Hong Kong's overall air quality in 2024 remained good andbroadly complied with Hong Kong's Air Quality Objectives. Owing to the efforts of the Hong Kong Special Administrative Region Government over the years, Hong Kong's air quality has continued to improve over the past 20 years, resulting in over a 50 per cent reduction in long-term health risks.
From 2004 to 2024, the annual average concentrations of respirable suspended particulates (PM10), fine suspended particulates (PM2.5), nitrogen dioxide (NO2) and sulphur dioxide (SO2) in the ambient air have reduced by 45 per cent to 88 per cent, whereas the annual average concentrations of these pollutants at the roadside have reduced by 36 per cent to 88 per cent. The annual average concentration of ozone (O3) has also gradually turned steady in the past few years (see Annex 1 for details). The number of hours of reduced visibility has greatly reduced by 82 per cent from its level in 2004 (Annex 2).
The EPD launched the Air Quality Health Index (AQHI) in 2014 to provide the public with daily updates on short-term health risks of air pollution, enabling the individuals to take necessary precautions to safeguard their health. In 2024, the percentage of hourly AQHI readings below 7 (i.e. within the "low" or "moderate" health risk categories) recorded by general and roadside monitoring stations improved from 96.1 per cent and 92.1 per cent when the index was first launched in 2014 to 98.7 per cent and 98.9 per cent, respectively.
Despite the increase in regional ozone levels, the significant improvement in Hong Kong's air quality has resulted in a continuous reduction in the associated long-term health risks. From 2004 to 2024, the improvement in air quality has led to over a 50 per cent reduction in long-term health risks (Annex 3).
Making reference to health risk data from hospital admissions associated with air pollutants over the past decade, the EPD will update the relevant risk factors assigned to relevant air pollutants. The EPD will also update the compilation methods of AQHI with reference to the latest guideline levels for air pollutants as set out in the latest air quality guidelines published by the World Health Organization, thereby providing more accurate information and warning forecast. The updated AQHI will come into effect on March 22, 2025. Detailed information on the updates will be made available to the public via the dedicated AQHI websitewww.aqhi.gov.hk/en/index.html.
An EPD spokesman said, "With the Government's continued promotion and implementation of the comprehensive air quality improvement measures put forth in the Hong Kong Roadmap on Popularisation of Electric Vehicles, the Clean Air Plan for Hong Kong 2035 and Hong Kong's Climate Action Plan 2050 announced in 2021, and the Green Transformation Roadmap of Public Buses and Taxis announced in 2024, including the promotion of electric vehicles, green transport and net-zero electricity generation, the overall air quality in Hong Kong will improve continuously."
